This invention relates to the art of railways and, more particularly, to apparatus for loading and unloading railway cars.
The present invention finds particular utility in connection with loading and/or unloading railway ties from a gondola type railway car and, accordingly, will be described in detail herein in connection with such use. At the same time, it will be appreciated that the apparatus can be used in connection with the loading and/or unloading of materials other than railway ties from such a railway car, and for the loading and/or unloading of materials from other types of railway cars.
It is of course well known to fill a gondola car with new railway ties and to distribute the ties at locations along railway tracks where tie replacement operations are to take place. It is likewise well known that gondola cars are subsequently loaded with the replaced ties for the latter to be transported to a location or locations for disposal. Car loading and unloading apparatus has been provided for the foregoing purpose, including apparatus adapted to be supported on the top edges of the side walls of a gondola car to be loaded or unloaded, or an adjacent car, and having boom operated grapple means for achieving the loading and unloading operations. When a given car has been filled with ties, or emptied, the apparatus is transferred to another car in readiness for the next filling or emptying operation.
There are many advantages attendant to loading and unloading railway cars with such car supported equipment, including the fact that a number of coupled cars can be sequentially loaded or unloaded and, during such operations, moved along the tracks with the apparatus thereon to locations where the new ties are to be unloaded, or replaced ties loaded into the cars. Such car supported apparatus heretofore provided, however, are structurally complex and limited in versatility of operation and, in some instances, are limited with respect to the gondola cars with which the apparatus can be used and/or the condition of the cars. In this respect, for example, such apparatus has been provided with wheels or rollers engaging the top edges of the side walls of a gondola car to support the apparatus relative thereto. The wheel arrangements enable the apparatus to move along the car and from one car onto the top edges of the side walls of an adjacent car. Apparatus of this character, however, is limited with respect to variations in height and width between adjacent gondola cars, thus necessitating the use of cars within such limitations. Accordingly, a somewhat special group of gondola cars must be maintained for use with the apparatus in that those cars which might otherwise be available for a loading or unloading operation could not be negotiated by the apparatus. Additionally, the rolling of the apparatus along the top edges of the side walls of the gondola cars requires that both the walls and the top edges thereof be in good condition to facilitate rolling of the apparatus therealong and to assure adequate support for the apparatus. This too limits the gondola cars with which such apparatus can be used. The necessity of having to maintain a special group of cars for tie loading and unloading apparatus in effect eliminates the availability of the gondola cars for other uses. When it is considered that gondola cars are high demand cars in the railroad business, it will be appreciated that such restrictions on the use thereof are extremely undesirable. Still further, the construction of such apparatus to provide for the wheels or rollers to be manipulatable to enable movement of the apparatus from one car to another is relatively complex, whereby the apparatus is expensive to manufacture.
Another device heretofore provided for loading and unloading gondola cars while resting on the top edges of the side walls thereof employs a pair of beams extendng longitudinally of the railway car and along which a crane carriage is movable. Both the beams and the carriage are adapted to be supported on the top edges of the side walls of the car in a manner which enables the carriage to support the beams for displacement thereof relative to the carriage, and for the beams to support the carriage for movement therealong. Such support functions are alternated in operation to achieve movement of the apparatus along a car and across the space between adjacent cars. While apparatus of this character is more versatile than wheel supported apparatus with respect to use with gondola cars having different height and width dimensions, it is structurally complex, heavy, and expensive to manufacture.
Still further, apparatus heretofore provided for loading and unloading gondola cars while resting on the top edges of the side walls thereof are limited either with respect to the height to which the gondola car can be filled with ties, or the direction of movement of the apparatus relative to the cars being loaded or unloaded. In this respect, if a given car is loaded with ties to a height above the side walls of the car, such material height will interfere with movement of the apparatus along the car, whereby loading or unloading must progress with respect to one direction of relative movement between the apparatus and cars. If the versatility of moving along a car in either direction is desired, then the height of loading must be less than would otherwise be possible, thus reducing the potential load capacity for a given string of cars. Further, should it be desired to keep the apparatus in a given location following a loading or unloading operation, either one car of the string must be left behind to support the apparatus, or the apparatus must be removed from the string of cars to a position along side the railway tracks. The latter undesirably requires special handling equipment, and to leave one car behind undesirably reduces the load capacity otherwise available for the string of cars. Still further, when it becomes desirable to transport the apparatus from one location to another, such transportation with the apparatus on the gondola car is undesirable from the standpoint of stability, and may be impossible because of the overall height of the car and apparatus. While the latter problems can be avoided by transporting the apparatus such as on a flat car, for example, transfer of the apparatus from a gondola car to such a flat car requires special equipment for lifting the apparatus from the gondola car and lowering the apparatus onto the flat car, which equipment must of course be available or made available. All of these disadvantages adversely affect the cost and efficiency of railway tie handling operations, or any other car loading or unloading operations using such equipment.